Add "silent call" feature to OpenBSC
This allows the administrator to use the vty interface to issue a silent
call to a given subscriber by using
"subscriber extension XXXX silent call start"
and stopping that silent call with
"subscriber extension XXXX silent call stop"
diff --git a/openbsc/src/silent_call.c b/openbsc/src/silent_call.c
new file mode 100644
index 0000000..3161834
--- /dev/null
+++ b/openbsc/src/silent_call.c
@@ -0,0 +1,92 @@
+/* GSM silent call feature */
+
+/*
+ * (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <openbsc/msgb.h>
+#include <openbsc/signal.h>
+#include <openbsc/debug.h>
+#include <openbsc/paging.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/gsm_subscriber.h>
+#include <openbsc/abis_rsl.h>
+
+static int paging_cb_silent(unsigned int hooknum, unsigned int event,
+ struct msgb *msg, void *_lchan, void *_data)
+{
+ struct gsm_lchan *lchan = _lchan;
+ struct scall_signal_data sigdata;
+ int rc;
+
+ if (hooknum != GSM_HOOK_RR_PAGING)
+ return -EINVAL;
+
+ DEBUGP(DSMS, "paging_cb_silent: ");
+
+ sigdata.lchan = lchan;
+ sigdata.data = _data;
+
+ switch (event) {
+ case GSM_PAGING_SUCCEEDED:
+ DEBUGPC(DSMS, "success, using Timeslot %u on ARFCN %u\n",
+ lchan->ts->nr, lchan->ts->trx->arfcn);
+ /* increment lchan reference count */
+ dispatch_signal(SS_SCALL, S_SCALL_SUCCESS, &sigdata);
+ use_lchan(lchan);
+ break;
+ case GSM_PAGING_EXPIRED:
+ DEBUGP(DSMS, "expired\n");
+ dispatch_signal(SS_SCALL, S_SCALL_EXPIRED, &sigdata);
+ break;
+ default:
+ rc = -EINVAL;
+ break;
+ }
+
+ return rc;
+}
+
+int gsm_silent_call_start(struct gsm_subscriber *subscr, void *data)
+{
+ int rc;
+
+ rc = paging_request(subscr->net, subscr, RSL_CHANNEED_TCH_F,
+ paging_cb_silent, data);
+ return rc;
+}
+
+int gsm_silent_call_stop(struct gsm_subscriber *subscr)
+{
+ struct gsm_lchan *lchan;
+
+ lchan = lchan_for_subscr(subscr);
+ if (!lchan)
+ return -EINVAL;
+
+ /* FIXME: did we actually establish a silent call for this guy? */
+ put_lchan(lchan);
+
+ return 0;
+}